A long-life service method for powder-bottom-injecting converter based on collaborative hot replacement of furnace bottom and bottom purging brick belongs to the field of steelmaking technologies using powder-bottom-injecting converters. According to equipment characteristics, process characteristics, and erosion characteristics of the powder-bottom-injecting converter, the design, arrangement, installation, use, maintenance, and replacement of the bottom purging/powder injection bricks are systematically optimized and improved, a technology of automatically detecting the erosion height of bottom purging bricks is adopted, and hot replacement of bottom purging/powder injection bricks and hot replacement of the converter furnace bottom are used collaboratively, which not only can prolong the service life of a single bottom purging/powder injection brick, but also can greatly prolong the overall life of the powder-bottom-injecting converter from 1000-3000 heats in the prior art to 6000-10000 heats. Hence, the life of the powder-bottom-injecting converter is as long as that of a conventional converter.

A top-blowing lance nozzle is configured to freely switch an adequate expansion condition so as to control an oxygen-blowing amount and a jetting velocity independently of each other without requiring a plurality of lance nozzles or a mechanically movable part. A lance nozzle is configured to blow refining oxygen to molten iron charged in a reaction vessel while a gas is blown from a top-blowing lance to the molten iron. One or more blowing holes for blowing a working gas are on an inner wall side surface of the nozzle, at a site where the lance nozzle has a minimum cross-sectional area in a nozzle axis direction or at a neighboring site of the site.

A burner comprises a primary nozzle for injecting an oxygen-rich gas. The primary nozzle is designed as a supersonic nozzle. A coaxial nozzle having an annular outlet opening is provided for injecting a fuel gas. The coaxial nozzle is designed as a subsonic nozzle and is coaxial to the primary nozzle. The primary nozzle has a convergent portion and a divergent portion, which adjoin each other at a radius of the narrowest cross-section. The annular outlet opening is located at an end face of the burner. The fuel gas, in the form of hydrogen or a mixture of hydrogen and a hydrocarbon-containing gas, is injected at a fixed inlet pressure and a fixed inlet volumetric flow rate, with respect to a planned thermal power of the burner. In contrast, the inlet pressure and the inlet volumetric flow rate of the oxygen-rich gas are varied according to the application.

A blast furnace for ironmaking production wherein iron ore is at least partly reduced by a reducing gas which is injected in the stack of the blast furnace. The blast furnace includes an external and an internal wall, having a thickness T.sub.int, in contact with matters charged into the blast furnace. The thickness T.sub.int of the internal wall is substantially constant above and below the injection area of a reducing gas.

A lance (1) for blowing oxygen onto a bath of molten steel including a tip (15) provided with first oxygen ejector (16) and a distributor (17) provided with second ejector (18).

A tuyere comprising an inner tube including a lower section having a first diameter, an upper section having a second diameter smaller than the first diameter, and a converging transition section having a converging angle Θ from 30° to 60° connecting the lower section to the upper section, the inner tube terminating in an inner nozzle at a downstream end of the upper section; and an outer tube surrounding the inner tube so as to create an annulus there between, the outer tube including a lower section having a third diameter larger than the first diameter, an upper section having a fourth diameter smaller than the third diameter but larger than the second diameter, and a converging transition section having connecting the lower section to the upper section, the outer tube terminating in an outer nozzle at a downstream end of the upper section.

A concentrate burner provided over a reaction shaft of a copper smelting furnace, is characterized by comprising: a raw material supply portion that supplies a starting material into the reaction shaft, the starting material including copper concentrate; and an additive supply portion that is provided separately from the raw material supply portion and supplies solid additive to the starting material.

An injector configured to be placed in a process chamber of a batch furnace assembly for injecting a gas into said process chamber. The injector has an elongated, tubular housing enclosing an injection chamber. The housing has a gas inlet opening for supplying a gas from a gas source to the injection chamber, at least one gas supply opening for supplying the gas from the injection chamber into the process chamber, and a circumferential wall extending in a longitudinal direction of the housing. The circumferential wall comprises a first lateral wall half and a second lateral wall half. Both lateral wall halves substantially span a length of the housing in the longitudinal direction. The first and second lateral wall halves are fastened to each other by means of mechanical fastening.

A tuyere comprising an inner tube including a lower section having a first diameter, an upper section having a second diameter smaller than the first diameter, and a converging transition section having a converging angle from 15 to 35 connecting the lower section to the upper section, the inner tube terminating in an inner nozzle at a downstream end of the upper section; and an outer tube surrounding the inner tube so as to create an annulus there between, the outer tube including a lower section having a third diameter larger than the first diameter, an upper section having a fourth diameter smaller than the third diameter but larger than the second diameter, and a converging transition section having connecting the lower section to the upper section, the outer tube terminating in an outer nozzle at a downstream end of the upper section.

The present invention preferably comprises a system and method for operating and/or positioning a lance and nozzle assembly relative to a molten metal bath in a vessel. Specifically, at least one temperature sensor is provided proximate a tip of the lance and nozzle assembly and at least one temperature sensor is provided on or in the vessel. A processing unit is configured to receive at least one signal from each of the temperature sensors, process the signals to determine the active position of the lance and nozzle assembly relative to the metal bath, and move the lance and nozzle assembly to a preferred position the corresponds to a stage of operation in the vessel.